Method and apparatus for peritoneal distension

Abstract

The present invention is a method and apparatus for performing peritoneal distension. The method includes providing a support structure on a surgical table, wherein the support structure includes a substantially vertical post and an arm assembly. A distal end of the arm assembly is positioned over a patient on the surgical table while the vertical post remains stationary. A peritoneal distension instrument extending from the arm assembly is coupled to a peritoneal structure of the patient. The peritoneum of the patient is distended by vertically raising the arm assembly while the post remains stationary relative to the surgical table. The apparatus is a surgical instrument support structure including a substantially vertical post having a gear rack disposed generally along the post's axis and an arm assembly movably coupled along the gear rack extending from the gear rack for holding a surgical instrument. The arm assembly includes a circular gear rotatably coupled to the arm assembly in engagement with the gear rack and a mechanism for rotating the circular gear, whereby rotation of the circular gear raises and lowers the arm assembly relative to the vertical post.

What is claimed is: 
     
       1. A method for peritoneal distension comprising the steps of: providing a support structure on a surgical table, the support structure including a substantially vertical post and an arm assembly;   positioning a distal end of the arm assembly over a patient on the surgical table while the vertical post remains stationary;   coupling a peritoneal distension instrument extending from the arm assembly to a peritoneal structure of the patient;   vertically raising the arm assembly while the post remains stationary relative to the surgical table, thereby distending the peritoneum of the patient; and   locking the arm assembly to the vertical post at a preselected height.   
     
     
       2. The method of claim 1 wherein locking the arm assembly to the vertical post includes: placing a load on the distal end of the arm assembly to frictionally bind the arm assembly to the vertical post at a selected height.   
     
     
       3. The method of claim 1 wherein the vertical post includes a gear rack along its axis, wherein the arm assembly includes a gear member movably coupled to the arm assembly and engaging the gear rack and wherein the step of locking the arm assembly to the vertical post includes: locating a pin coupled to the gear member within a detent defined by the arm assembly to prevent movement of the gear member and to lock the arm assembly to the vertical post at a selected height.   
     
     
       4. The method of claim 1 wherein the vertical post includes a gear rack and wherein the arm assembly includes a circular gear member movably coupled to the arm assembly and engaging the gear rack, wherein the step of vertically raising the arm assembly includes: moving the circular gear member, whereby movement of the gear member raises the arm assembly relative to the gear rack.   
     
     
       5. The method of claim 1 further including the step of: rotating a distal portion of the arm assembly about an axis of the distal portion to relocate the distal portion relative to the peritoneum of the patient.   
     
     
       6. A method for peritoneal distension comprising the steps of: providing a support structure on a surgical table, the support structure including a substantially vertical post and an arm assembly wherein the arm assembly includes a circular gear member movably coupled to the arm assembly and engaging the gear rack;   positioning a distal end of the arm assembly over a patient on the surgical table while the vertical post remains stationary;   coupling a peritoneal distension instrument extending from the arm assembly to a peritoneal structure of the patient; and   vertically raising the arm assembly while the post remains stationary relative to the surgical table by moving the circular gear member, whereby movement of the gear member raises the arm assembly relative to the gear rack, thereby distending the peritoneum of the patient.   
     
     
       7. The method of claim 6 further including the step of: locking the arm assembly to the vertical post at a preselected height.   
     
     
       8. The method of claim 7 wherein locking the arm assembly to the vertical post includes: placing a load on the distal end of the arm assembly to frictionally bind the arm assembly to the vertical post at a selected height.   
     
     
       9. The method of claim 7 wherein the vertical post includes a gear rack along its axis, wherein the arm assembly includes a gear member movably coupled to the arm assembly and engaging the gear rack and wherein the step of locking the arm assembly to the vertical post includes: locating a pin coupled to the gear member within a detent defined by the arm assembly to prevent movement of the gear member and to lock the arm assembly to the vertical post at a selected height.   
     
     
       10. The method of claim 6 further including the step of: rotating a distal portion of the arm assembly about an axis of the distal portion to relocate the distal portion relative to the peritoneum of the patient.